CVE-2024-7447 Overview
CVE-2024-7447 affects the Funnelforms Free plugin for WordPress, an interactive contact and multi-step form builder. The plugin fails to enforce a capability check on the fnsf_af2_handel_file_upload function. Unauthenticated attackers can upload arbitrary media files to a vulnerable site, even when no forms have been created. The flaw affects all versions up to and including 3.7.3.2 and is tracked as a missing authorization weakness [CWE-862]. It carries a network-based attack vector with low integrity impact and no privileges required.
Critical Impact
Unauthenticated attackers can upload arbitrary media files to WordPress sites running Funnelforms Free <= 3.7.3.2, enabling content pollution and potential downstream abuse.
Affected Products
- Funnelforms Free plugin for WordPress, all versions through 3.7.3.2
- WordPress sites with the plugin installed and activated
- WordPress environments that expose plugin AJAX endpoints to unauthenticated users
Discovery Timeline
- 2024-08-28 - CVE-2024-7447 published to the National Vulnerability Database (NVD)
- 2026-06-17 - Last updated in the NVD database
Technical Details for CVE-2024-7447
Vulnerability Analysis
The vulnerability is a missing authorization flaw in the Funnelforms Free plugin's file upload handler. The fnsf_af2_handel_file_upload function processes uploads without validating the caller's capabilities or verifying a valid nonce tied to an authenticated session. Any client that can reach the plugin's AJAX endpoint can invoke the handler and store files in the WordPress media library. The issue is classified as Missing Authorization [CWE-862] and impacts data integrity because attackers introduce unsanctioned content into the site.
Root Cause
The root cause is the absence of a current_user_can() capability check inside the file upload handler. WordPress plugins that accept uploads must confirm the caller holds an appropriate capability, such as upload_files, before invoking wp_handle_upload or writing to the media library. The Funnelforms Free code path skips this validation, treating the upload endpoint as public. Reviewers can inspect the affected logic in the Funnelforms Free frontend source.
Attack Vector
An attacker sends a crafted HTTP POST request to the plugin's AJAX action from any unauthenticated context. The request includes a multipart file payload targeting the vulnerable handler. Because no capability check runs, the plugin accepts the upload and stores it in the WordPress uploads directory. Attackers can abuse this to seed the site with malicious content, host phishing assets, exhaust storage, or stage files that support secondary attacks against site administrators. Technical detail is available in the Wordfence vulnerability report.
Detection Methods for CVE-2024-7447
Indicators of Compromise
- Unexpected files appearing in wp-content/uploads/ that do not correspond to editorial activity or known form submissions.
- HTTP POST requests to admin-ajax.php referencing the fnsf_af2_handel_file_upload action from unauthenticated clients.
- New attachments in the WordPress media library with no associated authenticated user or post reference.
Detection Strategies
- Review web server access logs for POST requests to wp-admin/admin-ajax.php that carry the vulnerable action name and lack an authenticated session cookie.
- Compare the installed Funnelforms Free version against the fixed release; any version at or below 3.7.3.2 is vulnerable.
- Audit the WordPress media library for attachments uploaded outside normal editorial workflows, especially files with executable or script-adjacent extensions.
Monitoring Recommendations
- Alert on spikes in unauthenticated POST traffic to WordPress AJAX endpoints tied to the Funnelforms plugin.
- Monitor disk consumption in the uploads directory to detect bulk file upload abuse.
- Track plugin inventory across managed WordPress sites and flag installations pinned to vulnerable versions.
How to Mitigate CVE-2024-7447
Immediate Actions Required
- Update Funnelforms Free to a version later than 3.7.3.2 that includes the fix from WordPress changeset 3141470.
- Deactivate and remove the plugin if an updated version cannot be applied promptly.
- Audit the uploads directory and media library for unauthorized files introduced while the plugin was vulnerable.
Patch Information
The plugin developer addressed the missing capability check in the trunk update recorded in WordPress changeset 3141470. Site administrators should upgrade the plugin through the WordPress admin dashboard or via WP-CLI to apply the fix. Confirm the running version after upgrade and verify that the media library no longer accepts uploads from unauthenticated sessions.
Workarounds
- Restrict access to admin-ajax.php at the web application firewall (WAF) layer, blocking unauthenticated requests that reference the fnsf_af2_handel_file_upload action.
- Apply server-level access controls to the plugin's frontend endpoints until the patch can be deployed.
- Disable the plugin entirely on sites where forms are not in active use.
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
